Surgery USLME\ Part 2 \ 251-500

251. A 37-year-old woman is brought to the surgical floor after undergoing a routine vaginal hysterectomy that morning. She had been fasting since midnight the night prior to her surgery. She has no past medical history except for uterine fibroids and takes only oral contraceptive pills regularly. During the procedure, she was reported to lose approximately 300 mL of blood. On the floor, she appears well but complains of some fatigue. Her blood pressure is 110/60 mm Hg, and her pulse is 100/min. She is not taking food or water yet because of persistent nausea and vomiting postoperatively. Which of the following is the most appropriate next step in management?

252. A window cleaner falls from a third-story scaffold and lands on his feet. Physical examination and x-rays show comminuted fractures of both calcaneus. He is tender to palpation over multiple bruises and abrasions in other parts of his trunk and extremities, but he has normal vital signs and a normal neurologic exam. Given the mechanism of injury, which of the following is the most appropriate next step in diagnosis?

253. On the second postoperative day after an abdomino-perineal resection for cancer of the rectum, a 72-yearold man complains of severe retrosternal pain. The pain is crushing in nature and radiates to the left arm. He also becomes short of breath and tachycardic. Except for his fresh surgical wounds and postoperative discomfort, physical examination is unremarkable. He does not have distended neck veins. Which of the following is the most appropriate next step in diagnosis?

254. A 14-year-old girl has a firm, movable, rubbery mass in her left breast. The mass was first noticed 6 months ago and has since grown to about 6 cm in diameter. Which of the following is the most likely diagnosis?

255. A 3-week-old infant is brought in because of 2 days of protracted bilious vomiting. He looks acutely ill, and plain x-rays show two large air fluid levels in the upper abdomen, the larger one on the left side and a smaller one on the right side. The radiologist describes the finding as a "double bubble sign." He also reports that there is intraluminal gas distal to those two air fluid levels, but that it is sparse and does not outline distended loops. Which of the following is the most likely tentative clinical diagnosis?

256. A 43-year-old man with a gangrenous gallbladder and gram-negative sepsis agrees to participate in a research study. An assay of tumor necrosis factor (TNF) is performed. Which of the following is the origin of this peptide?

257. A 49-year-old man who underwent liver transplantation 5 years ago for alcoholic cirrhosis presents with a gradually increasing bilirubin level. He undergoes a liver biopsy, which demonstrates a paucity of bile ducts. Which of the following is his best option for treatment?

258. An otherwise healthy 24-year-old man presents in the emergency department with very severe pain of recent onset in his right scrotum. The pain is constant and began about 3 hours prior to his arrival. Physical examination shows a temperature of 39.4 C (103 F) but is otherwise unremarkable, except for the scrotal area. The testis on the affected side is in the normal position; however, it appears to be swollen and is exquisitely tender to palpation. The cord above the testis is equally painful and tender. Urinalysis shows pyuria. Which of the following is the most appropriate next step in management?

259. A 16-year-old boy is persuaded by his older brother to accompany him and his friends on a beer-drinking binge. This is the first such experience for the boy, and it leads to the development of severe colicky left flank pain. When rescued by his parents, he is diaphoretic and doubled up in pain. He relates that he began to urinate frequently and profusely after the third or fourth beer and that the pain seized him shortly thereafter. He is tender to fist percussion over the left costovertebral angle but is afebrile. Which of the following is the most likely diagnosis?

260. A 25-year-old man is found on a pre-employment chest x-ray film to have a 3-cm peripheral coin lesion. The patient has never smoked, and a chest x-ray film that he had 2 years ago when he enrolled in graduate school had been normal. Prompted by this finding, he undergoes a more thorough physical examination, which discloses the presence of a firm, 2-cm testicular mass of which he was not previously aware. There are also palpable inguinal nodes on the same side. Which of the following is the most appropriate next step in management?

261. A 53-year-old man is brought to the emergency department by his wife because of headache and visual changes. Approximately 3 hours ago, he had the acute onset of an extremely severe posterior headache that was non-radiating but was associated with nausea and vomiting. This headache subsided, but over the past hour he has developed mild neck stiffness and pain on flexion of his neck. The patient is not cooperative, so no additional history is known; however, his wife states that he was feeling well until recently and has no allergies. The patient appears moderately uncomfortable and is complaining of the worst headache he has ever experienced. Which of the following is the most likely cause for hissymptoms?

262. A 25-year-old man is shot with a .22-caliber revolver. The entrance wound is in the anterior, lateral aspect of his thigh, and the bullet is seen on x-ray films to be embedded in the muscles posterolateral to the femur. The emergency department physician cleans the wound thoroughly. Which of the following is the most appropriate next step in management?

263. A patient sustained third-degree burns on both his arms when his shirt caught on fire while he was lighting the backyard barbecue. The burned areas are dry, white, leathery, anesthetic, and circumferential all around the arms and forearms. Which of the following parameters should be very closely monitored?

264. A previously healthy 60-year-old man is referred for urologic evaluation of macroscopic hematuria. Urinary cytology is positive for malignant cells, and cystoscopic examination reveals an exophytic multifocal tumor. A biopsy of die tumor demonstrates papillary fronds lined by ccfls similar to transitional epithelium but showing nuclear atypia, mitoses, and necrosis. Which of the following is the most important risk factor in the U.S. For the development of this type of tumor?

265. A young man is brought to the emergency department following a head-on collision at 30 miles per hour. He is awake and alert. Other than a forehead laceration, physical examination is normal and laboratory values are within normal limits. Chest x-ray films are unremarkable. Which of the following is the most appropriate next step in diagnosis?

266. A 52-year-old woman in renal failure is listed as a transplant candidate. In order to assess the propriety of the transplant, which of the following combinations represents how a cross-match is performed?

267. A 25-year-old man presents with a painless, hard, 3-cm testicular mass that he discovered serendipitously while taking a shower. Physical examination confirms that the mass arises from the testicle itself, is not part of the epididymis, and is solid rather than a fluid collection. The rest of the physical examination is unremarkable. Which of the following would be the most appropriate next step?

268. A 72-year-old man has a 4-cm hard mass in the left supraclavicular area. The mass is movable and nontender and has been present and steadily growing for the past 3 months. On direct questioning the only additional findings include a 20-pound weight loss and a vague feeling of epigastric discomfort over the past 2 months. Physical examination shows evidence of the weight loss but no other significant findings in the abdominal examination. The supraclavicular mass is obvious, but no other masses can be felt anywhere else in the neck, axillas, or groins. There is occult blood in the stool, and his hemoglobin is 10.5 g/dL. Which of the following would a biopsy of the supraclavicular mass most likely reveal?

269. A 65-year-old man comes to the physician for a health maintenance examination. Which of the following screening methods would allow the highest detection rate of prostatic carcinoma in early stages?

270. A 22-year-old woman is brought to the emergency department after a motorcycle accident in which she sustained severe crush injuries of her lower extremities. In the field, her Glasgow Coma Score was 14. She is awake and alert on arrival after having been given morphine for pain control. Any details of her past medical history are unknown. Initial examination shows a blood pressure of 140/80 mm Hg and pulse of 100/min. Her oxygen saturation on room air is 95% by pulse oximeter. An ECG is obtained and shows very large, peaked T-waves in leads V1-V6. Which of the following is the most appropriate initial step in patient care?

271. A 53-year-old woman sustains multiple injuries in a head-on automobile collision. She was driving the car and wearing a seat belt. At the moment of impact, she was held in place by the belt, but she hit the windshield with her face, the dashboard with her arms, and the steering wheel with her abdomen. Initial survey reveals closed fractures in both upper extremities, facial lacerations, and abdominal bruises. She is breathing well and is neurologically intact, but she is complaining of severe abdominal pain. Her blood pressure is 75/55 mm Hg, pulse is 110/min, and central venous pressure is zero. Physical examination of the abdomen shows tenderness, guarding, and rebound tenderness on all quadrants. There is no evidence of pelvic fracture. Which of the following would be the most appropriate study to evaluate her abdominal injuries?

272. A 42-year-old man sustains a gunshot wound to the abdomen and is in shock. Multiple units of packed red blood cells are transfused in an effort to resuscitate him. He complains of numbness around his mouth and displays carpopedal spasm. An electrocardiogram demonstrates a prolonged QT interval. Which of the following is the most appropriate treatment?

273. A 6-year-old boy has insidious development of limping with decreased motion in one hip. He complains occasionally of knee pain on that side. He walks into the office with an antalgic gait. Examination of the knee is normal, but passive motion of the hip is guarded. The child is afebrile, and the parents indicate that his gait and level of activity were completely normal all his life until this recent problem. He has not had a recent febrile illness. Which of the following is the most likely diagnosis?

274. A 39-year-old woman is involved in a head-on, highspeed automobile collision. She arrives at the emergency department in a deep coma, with bilaterally fixed dilated pupils. She has normal blood pressure and pulse rate. CT scan of the head shows diffuse blurring of the gray-white interface and multiple small punctate hemorrhages. There is no single large hematoma or displacement of the midline structures. Extension of the CT to include the neck shows no cervical spine fractures. Which of the following is the most appropriate initial step in management?

275. A 32-year-old man undergoes a distal pancreatectomy, splenectomy, and partial colectomy for a gunshot wound to the left upper quadrant of the abdomen. One week later he develops a shaking chill in conjunction with a temperature spike of 39.4°C (103°F). His blood pressure is 70/40 mm Hg, pulse is 140 beats per minute, and respiratory rate is 45 breaths per minute. He is transferred to the intensive care unit (ICU), where he is intubated and a Swan-Ganz catheter is placed. Which of the following is consistent with the expected initial Swan-Ganz catheter readings?

276. An 82-year-old man develops severe abdominal distention, nausea, vomiting, and colicky abdominal pain. He has not passed any gas or stools for the past 12 hours. His vital signs are normal, and his pulse is regular. He has a distended, tympanitic abdomen, with hyperactive, highpitched bowel sounds. There are no signs of peritoneal irritation. Rectal examination is negative for masses or occult blood, and trie rectal vault is empty. Abdominal xray films show distended loops of small and large bowel, as well as a very large round gas shadow that is located in the right upper quadrant and tapers toward the left lower quadrant in the shape of a parrot's beak. The patient has never had any abdominal surgery, and he does not have any palpable hernias. Which of the following is the most appropriate next step in management?

277. A 42-year-old woman drops a hot iron on her lap while doing the laundry. She comes in with the shape of the iron clearly delineated on her upper thigh. The area is white, dry, leathery, and anesthetic. Which of the following is the most appropriate next step in management?

278. A 73-year-old woman with a long history of heavy smoking undergoes femoral artery-popliteal artery bypass for rest pain in her left leg. Because of serious underlying respiratory insufficiency, she continues to require ventilatory support for 4 days after her operation. As soon as her endotracheal tube is removed, she begins complaining of vague upper abdominal pain. She has daily fever spikes of 39°C (102.2°F) and a leukocyte count of 18,000/mL. An upper abdominal ultrasonogram reveals a dilated gallbladder, but no stones are seen. A presumptive diagnosis of acalculous cholecystitis is made. Which of the following is the next best step in her treatment?

279. A 72-year-old man has multiple injuries and an altered sensorium after a high-speed motor vehicle collision. He is intubated for his decreased mental status. During intubation, a large amount of gastric contents are noted in the posterior pharynx and he aspirates. Which of the following is the appropriate initial treatment?

280. A patient with severe neurological devastation after head trauma has a prolonged course in the intensive care unit. He has been mechanically ventilated for his entire hospital stay. Which of the following clinical findings is diagnostic of a ventilator-associated pneumonia?

281. A 40-year-old obese woman, mother of five children, presents with progressive jaundice that she first noticed 4 weeks ago. She has a total bilirubin of 22 mg/dL, with 16 mg/dL direct (conjugated) and 6 mg/dL indirect (unconjugated). Her transaminases (AST and ALT) are minimally elevated, but her alkaline phosphatase is about 6 times the upper limit of normal. She has no anemia or occult blood in the stools. She has a history of multiple episodes of colicky right upper quadrant abdominal pain, brought about by the ingestion of fatty food; the last episode occurred a few days before her jaundice was first noted. She currently has no pain and is afebrile. A sonogram of her upper abdomen shows a contracted gallbladder full of stones, as well as dilated intrahepatic and extrahepatic biliary ducts; however, no stone can be identified in die common duct. Which of the following is the most appropriate next step in diagnosis?

282. A patient involved in a car accident sustains burst fractures of several thoracic vertebral bodies. At the time of admission, he has no neurologic function at all below the level of the injury and he has flaccid sphincters. After a few days, there is partial recovery of function; the remaining deficits are loss of motor function and loss of pain and temperature sensation on both sides distal to the injury, with preservation of vibratory and positional senses. Which of die following is the most likely diagnosis?

283. A 51-year-old man is undergoing abdominal surgery and becomes hypotensive while under general anesthesia. The patient had been doing well during most of the procedure but now has a blood pressure of 80/40 mm Hg. His past medical history is significant for coronary artery disease and diabetes mellitus. A pulmonary artery catheter placed prior to the procedure gives the following data: Central venous pressure 10 mmHg, Pulmonary artery pressure 60/30 mmHg, Pulmonary capillary occlusion 24 mm Hg pressure Cardiac output 2.3 L/min. Which of the following is the most likely diagnosis?

284. A 62-year-old man complains of perineal discomfort and reports that there are streaks of fecal soiling in his underwear. Four months ago, he had a perirectal abscess drained surgically. Physical examination shows a perineal opening in the skin lateral to the anus, and a cord-like tract can be palpated going from the opening toward the inside of the anal canal. Brownish purulent discharge can be expressed from the tract. Which of the following is the most likely diagnosis?

285. A 29-year-old woman presents with a 6-month history of erythema and edema of the right breast with palpable axillary lymphadenopathy. A punch biopsy of the skin reveals neoplastic cells in the dermal lymphatics. Which of the following is the best next step in her management?

286. A 50-year-old woman with a history of essential hypertension presents to the emergency department with sudden onset of a severe headache, nausea and vomiting, and photophobia. On examination, her BP is 160/100 mmHg. She is mildly confused and has nuchal rigidity, without focal neurologic signs. Which of the following is the most likely diagnosis?

287. A 50-year-old woman with a history of essential hypertension presents to the emergency department with sudden onset of a severe headache, nausea and vomiting, and photophobia. On examination, her BP is 160/100 mmHg. She is mildly confused and has nuchal rigidity, without focal neurologic signs. Once the diagnosis has been confirmed, Rupture cerebral aneurysm, which of the following is the next most important step in patient management?

288. A 35-year-old woman presents with a lump in the left breast. Her family history is negative for breast cancer. On examination the mass is rubbery, mobile, and nontender to palpation. There are no overlying skin changes and the axilla is negative for lymphadenopathy. An ultrasound demonstrates a simple 1-cm cyst in the area of the palpable mass in the left breast. Which of the following represents the most appropriate management of this patient?

289. A 55-year-old woman presents with a slow-growing painless mass on the right side of the neck. A fine-needle aspiration of the nodule shows a well-differentiated papillary carcinoma. A complete neck ultrasound demonstrates a 1-cm nodule in the right thyroid without masses in the contralateral lobe or lymph node metastasis in the central and lateral neck compartments. With regards to this patient, which of the following is associated with a poor prognosis?

290. Following significant head trauma, a 34-year-old woman undergoes a CT scan that demonstrates bilateral frontal lobe contusions of the brain. There is no midline shift. She has a GCS of 14. Which of the following is the best initial management of this patient?

291. A 72-year-old man of Norwegian ancestry has a contracted hand that can no longer be extended and placed flat on a table. The problem developed gradually, over many years. He complains of no pain or neurologic abnormalities and, to the extent that the deformity allows, can move his fingers at will. Physical examination demonstrates the deformity described and in addition shows the presence of palpable fascial nodules. Which of the following is the most likely diagnosis?

292. A 50-year-old man is admitted to the hospital with a UGI bleed from acute erosive gastritis, secondary to chronic nonsteroidal anti-inflammatory use. His hematocrit is 28%. With fluid resuscitation, his blood pressure normalizes, but he has a persistent hyperdynamic precordium, tachycardia, and flow murmur on auscultation. He complains of shortness of breath on ambulation. An ECG shows depressed ST-T segments. Which of the following is the next appropriate step in management?

293. A previously healthy 28-year-old woman develops significant postpartum hemorrhage, with a rapid drop in hematocrit to 18%. Despite aggressive IV fluid resuscitation, the patient has a persistent tachycardia, labile systolic blood pressure, and poor urine output. Ongoing resuscitation includes emergency transfusion with 2 units of O-negative packed red blood cells. During transfusion of the second unit, the patient develops chills, fever, vomiting, and hypertension. These symptoms are most likely the result of which of the following?

294. A 45-year-old man with poorly controlled hypertension presents with severe chest pain radiating to his back. An ECG demonstrates no significant abnormalities. A CT scan of the chest and abdomen is obtained, which demonstrates a descending thoracic aortic dissection extending from distal to the left sub-clavian take off down to above the iliac bifurcation. A Foley catheter is placed, and urine output is 30 to 40 cc/h. His feet are warm, with less than 2-second capillary refill. Which of the following is the most appropriate initial management?

295. A stockbroker in his mid-40s presents with complaints of episodes of severe, often incapacitating chest pain on swallowing. Diagnostic studies on the esophagus yield the following results: endoscopic examination and biopsy mild inflammation distally; manometry—prolonged high-amplitude contractions from the arch of the aorta distally, lower esophageal sphincter (LES) pressure 20 mm Hg with relaxation on swallowing; barium swallow 2 cm epiphrenic diverticulum. Which of the following is the best management option for this patient?

296. A 45-year-old woman underwent elective surgery for an inguinal hernia. In the postoperative recovery room, she developed nausea, vomiting, and acute abdominal pain. She has a history of systemic lupus erythematosus, pernicious anemia, type-1 diabetes, chronic low back pain, and uterine fibroids. Her preoperative medications include monthly vitamin B-12 injections, insulin, prednisone, hydroxychloroquine, and acetaminophen. Her blood pressure is 70/40 mm Hg and heart rate is 110/min. Initial laboratory studies show a blood glucose of 50 mg/dl. Which of the following is the most likely cause of her condition?

297. A 57-year-old man comes to the physician for a routine checkup. He complains of right-sided leg cramps accompanied by fatigue while walking. He also complains of occasional right thigh pain. He denies chest pain, syncope, nausea, and abdominal pain. His sexual performance has decreased over the past 1 year. His other medical problems include stage 3 chronic kidney disease, type 2 diabetes mellitus, hypertension, hyperlipidemia, gout, and gastroesophageal reflux disease. His blood pressure is 144/92 mm Hg, pulse is 67/min, and BMI is 29 kg/m2. Peripheral pulses are bilaterally palpable. There is a small ulcer at the base of the right great toe. The ankle-brachia! index (ABI) is 1.0 (normal: 1.0 - 1.3). His laboratory values are significant for a serum creatinine level of 2.2 mg/dl and an HbA1c level of 7.5% but otherwise unremarkable. Which of the following is the most appropriate next step in managing this patient's leg pain?

298. A 34-year-old woman is admitted to the hospital because of septic shock secondary to a urinary tract infection. In the intensive care unit, she receives intravenous fluids and antibiotics. Her initial ECG shows sinus tachycardia but is otherwise unremarkable. Chest x-ray shows no abnormalities. An internal jugular vein catheter is placed on the right side using ultrasound guidance to locate the vein. The patient is properly draped, and the skin is cleaned with chlorhexidine solution. Blood is freely aspirated from all ports after insertion. Vital signs are stable, and oxygenation is maintained. Which of the following is the most appropriate next step in managing this patient?

299. A 45-year-old woman, who wears high-heeled, pointed shoes, complains of pain in the forefoot after prolonged standing or walking. Occasionally, she also experiences numbness, a burning sensation, and tingling in the area. Physical examination shows no obvious deformities and a very tender spot in the third interspace, between the third and fourth toes. There is no redness, limitation of motion, or signs of inflammation. Which of the following is the most likely diagnosis?

300. A 22-year-old gang member arrives in the emergency department with multiple gunshot wounds to the chest and abdomen. He has labored breathing and is cyanotic, diaphoretic, cold, and shivering. He is wide awake, and in a normal tone of voice he tells everyone that he is going to die. An initial survey reveals a blood pressure of 60/40 mm Hg. His pulse is 150/min and barely perceptible. He is in obvious respiratory distress and has big distended veins in his neck and forehead. His trachea is deviated to the left, and the right side of his chest is hyperresonant to percussion, with no breath sounds. Which of the following is the most appropriate initial step in management?

303. A 55-year-old man with recent onset of atrial fibrillation presents with a cold, numb, pulseless left lower extremity. He is immediately taken to the operating room for an embolectomy of the left popliteal artery. Which additional procedure should be performed along with the embolectomy?

304. A 58-year-old man presents with pain in the left leg after walking more than one block that is relieved with rest. On physical examination, distal pulses are not palpable in the left foot and there is dry gangrene on the tip of his left fifth toe. An ankle-brachial index on the same side is 0.5. Which of the patient’s symptoms or signs of arterial insufficiency qualifies him for reconstructive arterial surgery of the left lower extremity?

306. An 84-year-old man is brought to the emergency department because of 1 hour of severe back pain. He also had syncope that lasted <1 minute. Before arriving at the hospital, he had an episode of gross hematuria, which he has never had before. He also complains of some shortness of breath. He denies chest pain, cough, nausea, vomiting, headache, and neck pain. His blood pressure is 72/55 mm Hg and pulse is 112/min and regular. His pulse oximetry shows 92% on room air. His ECG shows sinus tachycardia with prominent horizontal ST segment depression in the anterior chest leads. Which of the following is the most likely diagnosis?

307. A 23-year-old man known to have neurofibromatosis, type 1 (von Recklinghausen's disease), presents with a left lower quadrant abdominal mass and signs of neurologic deficits in his left leg. In the ensuing workup, it is determined that he has higher than normal values of catabolites of epinephrine and norepinephrine in a 24-hour urinary collection. He is currently normotensive. Before invasive steps are taken to biopsy and eventually remove his left lower quadrant abdominal mass, which of the following is the most appropriate next step in management?

308. A car is involved in a head-on collision. The driver, who is sober and wearing his seat belt, explains that he clearly saw his drunk, unrestrained front seat passenger hit the windshield with his face and the dashboard with his knees. Examination of the passenger indeed shows multiple facial lacerations, but because of his intoxication he cannot explain where else he might be hurting. He is neurologically intact, and his cervical spine x-ray films are normal. Additional injury, representing a potential orthopedic emergency, is not obvious but is suspected. Therefore, an x-ray film of which of the following areas should most likely be obtained?

309. A 35-year-old woman presents to the clinic for a discussion on breast cancer risk. Her family history is pertinent for a grandmother who died of breast cancer at age 53, a mother who died of premenopausal breast cancer, and one of three sisters with breast cancer diagnosed at age 42. The sister with breast cancer underwent genetic testing and was found to have a BRCA1 mutation. Subsequently, the 35-year-old woman underwent genetic testing and was found to be a carrier of the same deleterious BRCA1 mutation. Which of the following ranges represents the lifetime risk for breast cancer that should be quoted for this patient?

310. A 35-year-old woman presents to the clinic for a discussion on breast cancer risk. Her family history is pertinent for a grandmother who died of breast cancer at age 53, a mother who died of premenopausal breast cancer, and one of three sisters with breast cancer diagnosed at age 42. The sister with breast cancer underwent genetic testing and was found to have a BRCA1 mutation. Subsequently, the 35-year-old woman underwent genetic testing and was found to be a carrier of the same deleterious BRCA1 mutation. For this patient, which of the following strategies represent an accepted management option for her high-risk status?

311. A 38-year-old woman presents to the physician because of right upper quadrant pain associated with nausea and vomiting for the past 12 hours. She has had similar pain previously, usually precipitated after the ingestion of fatty foods. However, past episodes have always resolved within one to two hours. She has type 2 diabetes mellitus, hypertriglyceridemia, and hypercholesterolemia. Her current medications include metformin, fenofibrate, and a statin. Her temperature is 38.3° C (101° F), blood pressure is 130/70 mm Hg, pulse is 98/min, and respirations are 20/min. Her BMI is 32 kg/m2. Examination shows right upper quadrant tenderness. Abdominal ultrasound reveals gallstones, a thickened gallbladder wall with edema, and a normal common bile duct. Her alkaline phosphatase level is normal. Which of the following is the most appropriate next step in the management of this patient?

312. A 54-year-old man comes to the physician because of edema of his right ankle. He reports heaviness and cramping in the same leg that is worse after a long day at work. The swelling is usually reduced significantly when he wakes up in the morning and worsens progressively throughout the day. He denies any other symptoms. He has no significant medical problems except hypertension, for which he takes atenoloL His temperature is 36.7° C (98° F), blood pressure is 120/76 mm Hg, pulse is 80/min and respirations are 16/min. JVP is normaL Lungs are clear to auscultation. There are no murmurs. There is no hepatosplenomegaly. Examination shows edema of the right ankle. Doppler examination of the leg shows no evidence of thrombosis. Which of the following is the most likely cause of his edema?

313. A 40-year-old, obese, white woman, mother of five children, gives a history of repeated episodes of right upper quadrant abdominal pain. The pain is brought about by the ingestion of fatty foods and is relieved by the administration of anticholinergic medications. The pain is colicky, radiates to the right shoulder and around to the back, and is accompanied by nausea and occasional vomiting. The patient has no pain at this time, but is anxious to avoid further episodes. She is afebrile, and physical examination is unremarkable. Which of the following is the most appropriate next step in management?

314. A 68-year-old man presents to the physician’s office complaining of progressive dysphagia over the last 3 months associated with mild chest discomfort. He reports a 15-lb weight loss, a 30 pack-year smoking history, and occasional alcohol intake. The physical examination, including vital signs, is unremarkable. A chest x-ray was normal, and a barium esophagogram shows an irregular filling defect in the distal third of the esophagus with distortion and narrowing of the lumen. Which of the following is the most likely diagnosis?

315. A 68-year-old man presents to the physician’s office complaining of progressive dysphagia over the last 3 months associated with mild chest discomfort. He reports a 15-lb weight loss, a 30 pack-year smoking history, and occasional alcohol intake. The physical examination, including vital signs, is unremarkable. A chest x-ray was normal, and a barium esophagogram shows an irregular filling defect in the distal third of the esophagus with distortion and narrowing of the lumen. Which of the following is the most appropriate next step in management?

316. In this patient, a benign gastric ulcer was found, and he was placed on a proton-pump inhibitor and triple antibiotics for Helicobacter pylori. He returns to the physician’s office 3 months later with similar complaints and, on re-evaluation, the gastric ulcer was found to persist. Which of the following is the most appropriate next step in management?

318. A 29-year-old man presents with a 2-day history of severe left-sided scrotal pain and swelling. He is sexually active and has had "many" sexual partners. His temperature is 38.2 C (100.8 F), blood pressure is 120/70 mm Hg, and pulse is 80/min. Examination shows unilateral intrascrotal tenderness and swelling. Testicular support makes the pain less intense. Which of the following is the most likely diagnosis?

321. A 75-year-old woman with history of angina is admitted to the hospital for syncope. Examination of the patient reveals a systolic murmur best heard at the base of the heart that radiates into the carotid arteries. Electrocardiogram (ECG) is notable for left ventricular hypertrophy with evidence of left atrial enlargement. ECG reveals an aortic valve area of 0.7 cm2. What is the most appropriate next step in her management?

322. A 68-year-old man is diagnosed with lung cancer. In preparation for pulmonary resection he undergoes pulmonary function tests. Which of the following results indicate a favorable prognosis?

323. A 24-year-old man comes to the physician because of 1 week of abdominal pain. It is localized in the right lower quadrant and somewhat exacerbated by motion. Over the past 2 days, it has radiated to the back. He initially had two episodes of vomiting but now just has decreased appetite. He had one episode of diarrhea 1 day ago. He denies urinary frequency. His other medical problems include mild intermittent asthma and gastroesophageal reflux disease. He traveled to Mexico for 5 days 1 month ago and did not have any gastrointestinal symptoms during his stay there. His mother was diagnosed with colon cancer at the age of 49 years. His temperature is 38.2°C (100.8°F), blood pressure is 122/77 mm Hg, and pulse is 109/min and regular. Physical examination reveals prominent tenderness in the right lower quadrant, without rebound. Flexion of the right hip against resistance elicits significant abdominal pain. Laboratory results show: WBC count 16,000/mm' Hemoglobin 14.2 g/dl Platelet count 620,000/mm' Potassium 4.5 mEq/L Creatinine 1.0 mg/dl Which of the following is the most likely diagnosis?

324. A pediatrician's office gets a phone call from a frantic mother. Her 7-year-old daughter was playing under the sink and accidentally spilled Liquid Plumber (a strong, corrosive alkaline drain cleaner) all over her arms and legs. The nurse on the phone can hear the girl screaming in the background. Which of the following are the most appropriate instructions to give the mother?

325. A 59-year-old man sustains blunt trauma in an automobile accident, resulting in multiple intra-abdominal injuries. Surgery for the repair of these injuries takes several hours and requires multiple blood transfusions and infusions of Ringer's lactate. Before all the operative steps are completed, the patient develops a significant coagulopathy, a core body temperature less than 34 C (93.2 F), and refractory acidosis. The anesthesiologists are administering fresh frozen plasma and platelet packs. Which of the following is the most appropriate next step in management for the surgeon?

326. A previously healthy 19-year-old man presents to the emergency department with a penetrating wound to the right neck. There were reports of bleeding at the scene. The patient is talking, complaining of pain at the injury site and pain with swallowing. On examination, he has a normal respiratory rate, clear air entry on auscultation, blood pressure of 120/70 mmHg, and heart rate of 95 beats/min. There is a penetrating right neck wound in zone 2 (between the clavicle and the lower part of the mandible), with a surrounding hematoma. On probing, there is violation of the platysma. Which of the following is the best next step in the management of this patient?

327. A 45-year-old man is brought to the emergency department after being involved in an automobile crash. He is alert and oriented, with a normal neurologic examination. His respiratory rate is 20/min, with clear lungs, pulse rate of 120/min, and blood pressure of 80/40 mmHg. On examination, he is noted to have a distended abdomen, with decreased bowel sounds, and a fracture of the right ankle. IV access is established, and the patient receives a rapid infusion of 2 L of saline, without changes to pulse rate or blood pressure. Which of the following is the most appropriate next step in his management?

329. A 55-year-old man presents to the emergency department at 5 a.m. Complaining of vomiting blood. After binge drinking last night, the patient began to vomit repeatedly. After a number of episodes, the patient noted blood in the vomitus, followed by a melanotic stool 5 hours later. His past history is pertinent for ethanol abuse and a 40 pack-year smoking history. Vital signs reveal a BP of 100/60 mmHg, pulse rate of 95/min, respiratory rate of 12/min, and temperature of 97°F. Examination reveals a thin man with normal chest, cardiac, and abdominal findings. Rectal examination reveals heme-positive stool. Laboratory data show normal electrolytes and a hematocrit of 30. A chest x-ray is unremarkable. Volume resuscitation, gastric lavage, and NG tube decompression are initiated. Which of the following is the most appropriate diagnostic test?

330. A 70-year-old man with a 50 pack-year history of smoking presents with a 6-week history of intermittent, painless, gross hematuria and urinary frequency. There are no masses palpable on abdominal examination, and rectal examination is normal. Urinalysis confirms the presence of hematuria, and urine culture is negative. Which of the following is the most appropriate initial diagnostic evaluation of this patient?

331. A 70-year-old man with a 50 pack-year history of smoking presents with a 6-week history of intermittent, painless, gross hematuria and urinary frequency. There are no masses palpable on abdominal examination, and rectal examination is normal. Urinalysis confirms the presence of hematuria, and urine culture is negative. The initial diagnostic evaluation does not reveal any abnormalities. Which of the following is the best next step in the diagnostic workup?

333. Two days after admission to the hospital for a myocardial infarction, a 65-year-old man complains of severe, unremitting midabdominal pain. His cardiac index is 1.6. Physical examination is remarkable for an absence of peritoneal irritation or distention despite the patient’s persistent complaint of severe pain. Serum lactate is 9 mmol/L (normal is < 3 mmol/L). Which of the following is the most appropriate next step in this patient’s management?

334. A 55-year-old man comes to the emergency department because of severe retrosternal chest pain that suddenly started a few hours ago. He has been having some chest pain and epigastric burning for the past few days but says that the current pain is different. His other medical problems include nonischemic cardiomyopathy for which he takes furosemide, carvedilol, spironolactone, lisinopril, and potassium chloride. He also has HIV infection but has chosen not to take any medication related to this diagnosis. His temperature is 38.9° C (102° F), blood pressure is 110/65 mm Hg, pulse is 110/min, and respirations are 22/min. Examination shows that he is in obvious distress secondary to pain. His lungs are clear to auscultation. The remainder of the examination shows no abnormalities. His ECG is within normal limits. Chest x-ray shows a widened mediastinum and some mediastinal air. Which of the following is the most appropriate next step in the management of this patient?

335. A 36-year-old woman presents with palpitations, anxiety, and hypertension. Workup reveals a pheochromocytoma. Which of the following is the best approach to optimizing the patient preoperatively?

336. A 35-year-old woman is involved in a motor vehicle crash, sustaining a severe pelvic fracture, with disruption of the pelvic ring. In the trauma resuscitation room, she is confused and tachypneic, with a blood pressure of 90 mmHg systolic and a heart rate of 130/min. Laboratory investigations include serum electrolyte analysis, revealing a sodium of 139, a chloride of 103, and a bicarbonate of 14 meq/L. This patient demonstrates which of the following?

337. A 35-year-old woman is involved in a motor vehicle crash, sustaining a severe pelvic fracture, with disruption of the pelvic ring. In the trauma resuscitation room, she is confused and tachypneic, with a blood pressure of 90 mmHg systolic and a heart rate of 130/min. Laboratory investigations include serum electrolyte analysis, revealing a sodium of 139, a chloride of 103, and a bicarbonate of 14 meq/L. Which of the following is the most appropriate management of this acid-based derangement?

339. A 33-year-old pregnant woman notices a persistent, painless lump in the left breast. On examination the left breast has a single mobile mass without evidence of skin changes or lymphadenopathy in the neck or axilla. An ultrasound demonstrates a solid, 1-cm mass in the upper outer quadrant of the breast. A core-needle biopsy shows invasive ductal carcinoma. The patient is in her first trimester of pregnancy. Which of the following is the most appropriate management of this patient?

340. A 40-year-old woman presents with a rash involving the nipple-areola complex for the last month with associated itching. On physical examination there is crusting and ulceration of the nipple with surrounding erythema involving the areola and surrounding skin, no palpable breast masses, and no cervical or axillary lymphadenopathy. Which of the following is the most appropriate next step in the management of this patient?

341. A 54-year-old woman presents to her physician for an opinion regarding additional therapy following curative resection of recently diagnosed colon cancer. She underwent uncomplicated sigmoid resection for invasive colon cancer 4 weeks ago. The pathology revealed carcinoma invading into, but not through, the muscularis propria, with one of eight positive mesenteric nodes. There was no evidence of liver metastases at the time of operation. Preoperative chest x-ray and CT scan of the abdomen showed no evidence of distant disease. Preoperative carcinoembryonic antigen (CEA) level was normal. Past history is positive for diabetes and mild hypertension. Examination is unremarkable except for a healing abdominal incision. Which of the following is the correct stage of this patient’s colon cancer?

342. A 54-year-old woman presents to her physician for an opinion regarding additional therapy following curative resection of recently diagnosed colon cancer. She underwent uncomplicated sigmoid resection for invasive colon cancer 4 weeks ago. The pathology revealed carcinoma invading into, but not through, the muscularis propria, with one of eight positive mesenteric nodes. There was no evidence of liver metastases at the time of operation. Preoperative chest x-ray and CT scan of the abdomen showed no evidence of distant disease. Preoperative carcinoembryonic antigen (CEA) level was normal. Past history is positive for diabetes and mild hypertension. Examination is unremarkable except for a healing abdominal incision. Which of the following is the most appropriate recommendation regarding adjuvant therapy?

343. A 43-year-old man develops excruciating abdominal pain at 8:23 PM (he looked at his watch when the pain "hit him"). When seen in the emergency department about 30 minutes later, he has a rigid abdomen, lies motionless on the examination table, has no bowel sounds, and is obviously in great pain, which he describes as constant and encompassing the entire abdomen. There is very severe pain when deep palpation of the abdomen is attempted in any of the four quadrants. However, the examining hand cannot make much of an indentation because of the impressive muscle guarding. When the attempt is aborted, he manifests severe rebound tenderness. X-ray films show free air under both diaphragms. Which of the following does this man most likely have?

344. On the 5th postoperative day after abdominal surgery, a patient has been draining copious amounts of clear pink fluid from his midline laparotomy wound. A medical student removes the dressing, confirms that it is soaked, and sees a normal-appearing fresh wound with a row of skin staples in place. The student asks the patient to sit up so he can get out of bed and be helped to the treatment room for a more thorough examination. When the patient complies, the wound opens widely, and a handful of small bowel suddenly rushes out. Which of the following is the most appropriate management at this time?

345. Several days following esophagectomy, a patient complains of dyspnea and chest tightness. A large pleural effusion is noted on chest radiograph, and thoracentesis yields milky fluid consistent with chyle. Which of the following is the most appropriate initial management of this patient?

346. A 56-year-old woman presents for evaluation of a murmur suggestive of mitral stenosis and is noted on echocardiography to have a lesion attached to the fossa ovalis of the left atrial septum. The mass is causing obstruction of the mitral valve. Which of the following is the most likely diagnosis?

347. A 54-year-old man presents to the emergency department on transfer from another hospital at the request of the family. He was admitted to the outside hospital 2 weeks ago with abdominal pain, nausea, vomiting, and fever. He was treated with antibiotics, NG tube decompression, and TPN without significant improvement. He developed jaundice 2 days ago. His past history is pertinent for a 40 pack-year smoking history, chronic alcohol abuse, and diabetes. Examination reveals a mildly jaundiced patient with vital signs of temperature 100°F, pulse rate 95/min, and BP 110/60 mmHg. Cardiac examination is unremarkable, lung examination reveals decreased breath sounds at the bases bilaterally, and abdominal examination reveals fullness in the epigastrium with tenderness and voluntary guarding. Which one is the most likely diagnosis?

348. A 56-year-old woman presents to the physician’s office with complaints of a new left breast mass. She denies any pain, nipple discharge, or skin dimpling. She has a prior history of breast cysts 5 years ago, treated by aspiration at that time. Her last mammogram was at age 53. Past history is pertinent for a 30 pack-year smoking history, prior total abdominal hysterectomy bilateral salpingo-oophorectomy (TAH-BSO) at age 54 for leiomyomas, and current use of hormone replacement therapy (HRT). Family history is negative for breast disease. Examination reveals a firm, welldefined, mobile, 1.5-cm nodule in the upper outer quadrant of the left breast without any regional lymphadenopathy. Which of the following is the most appropriate next step in management?

349. A 54-year-old African American man, with a history of smoking and drinking, describes progressive dysphagia that began 3 months ago. He first noticed difficulty swallowing meat; it then progressed to other solid foods, then to soft foods, and now to liquids as well. He locates the place where the food "sticks" at the lower end of the sternum. He has lost 30 pounds. Which of the following is the most appropriate first step in diagnosis?

351. A 55-year-old man presents to the physician’s office for his yearly physical examination. He is asymptomatic. Past history is pertinent for hypertension. Family history is positive for breast cancer in his mother at age 70 and colon cancer in his father at age 65. His examination is unremarkable except for guiac positive stool. Barium enema shows a sigmoid colon polyp. Colonoscopy confirms a 3-cm pedunculated polyp in the sigmoid colon, and snare polypectomy is performed. Pathologic examination reveals an adenomatous polyp with a focus of invasive carcinoma in the head, with a 4-mm resection margin and no tumor noted in the stalk. Which of the following is the most appropriate next step in management?

353. An elderly woman with osteoporosis falls on her outstretched hand. She comes in with a deformed and painful wrist that looks like a dinner fork. X-ray films show a dorsally displaced, dorsally angulated fracture of the distal radius. There is also an associated fracture of the ulnar styloid. A neurologic examination is normal. Which of the following is the most appropriate management?

354. A 5-week-old infant presents with a 1-week history of progressive nonbilious emesis, associated with a 24-hour history of decreased urine output. The infant continues to be active and eager to feed. On examination, the infant has a sunken fontanelle and decreased skin turgor. The abdomen is scaphoid, and with a test feed, there is a visible peristaltic wave in the epigastrium. Which of the following is the most likely diagnosis?

355. A 5-week-old infant presents with a 1-week history of progressive nonbilious emesis, associated with a 24-hour history of decreased urine output. The infant continues to be active and eager to feed. On examination, the infant has a sunken fontanels and decreased skin turgor. The abdomen is scaphoid, and with a test feed, there is a visible peristaltic wave in the epigastrium. The diagnosis is best confirmed by which of the following?

357. A 75-year-old man is found by his internist to have an asymptomatic carotid bruit. Which of the following is the most appropriate next test?

358. An older, overweight man complains of disabling, sharp heel pain every time his foot strikes the ground. The pain is worse in the mornings, preventing him from putting any weight on the heel. X-ray films show a bony spur matching the location of his pain, and physical examination shows exquisite tenderness to direct palpation right over that heel spur. Furthermore, when the ankle is dorsiflexed, the entire inner border of the fascia is tender to palpation. Which of the following is the most likely diagnosis?

361. A 63-year-old man is seen because of facial swelling and cyanosis, especially when he bends over. There are large, dilated subcutaneous veins on his upper chest. His jugular veins are prominent even while he is upright. Which of the following conditions is the most likely cause of these findings?

362. During endoscopic biopsy of a distal esophageal cancer, perforation of the esophagus is suspected when the patient complains of significant new substernal pain. An immediate chest film reveals air in the mediastinum. Which of the following is the most appropriate management of this patient?

363. In preparation for an inguinal hernia repair, a 22-year-old man has a spinal anesthetic placed. The level of sensory block turns out to be much higher than had been planned, and shortly thereafter his blood pressure drops to 75/20 mm Hg. He looks warm and flushed, and his central venous pressure is near zero. Which of the following should be included in his therapy?

364. A 55-year-old woman presents with a 6-month history of weight loss, abdominal cramps, and intermittent nonbloody diarrhea. On examination, her abdomen is mildly distended and there is a palpable mass in the right lower quadrant. Stool cultures yield normal fecal flora. CT scan with oral contrast demonstrates an inflammatory mass in the right lower quadrant, with thickening of the terminal ileum and ileocecal valve. Which of the following is the most likely diagnosis?

365. A 55-year-old woman presents with a 6-month history of weight loss, abdominal cramps, and intermittent nonbloody diarrhea. On examination, her abdomen is mildly distended and there is a palpable mass in the right lower quadrant. Stool cultures yield normal fecal flora. CT scan with oral contrast demonstrates an inflammatory mass in the right lower quadrant, with thickening of the terminal ileum and ileocecal valve.Which of the following is the best diagnostic test to confirm the diagnosis?

366. A 27-year-old woman seeks your advice regarding pain and numbness in the right arm and hand. She reports that it is exacerbated by raising her arm over her head. On examination, the right radial pulse disappears when the patient takes a deep breath and turns her head to the left. A provisional diagnosis is made. Which of the following is the most appropriate initial treatment for this patient?

367. A 35-year-old man with a history of melanoma status post wide local excision with negative margins and lymph node dissection presents with 2, peripherallylocated pulmonary lesions seen on chest CT scan. Percutaneous biopsy of the lesion is consistent with metastatic melanoma. He has no evidence of recurrence or extrathoracic disease and is in good general health. Which of the following is the most appropriate management of this patient?

368. A 65-year-old woman has had pain in her right shoulder and has been treated with analgesics without relief. The CXR reveals a mass in the apex of the right chest. A transthoracic needle biopsy documents carcinoma. Superior pulmonary sulcus carcinomas (Pancoast tumors) are bronchogenic carcinomas that typically produce which of the following clinical features?

370. A 65-year-old man presents to the emergency department with sudden onset of pain and weakness of the left lower extremity of 2-hour duration. Past history reveals chronic atrial fibrillation following a myocardial infarction 12 months ago. On examination, he is found to have a cool, pale left lower extremity with decreased strength and absent popliteal and pedal pulses. The opposite leg has a normal appearance with palpable pulses. Which of the following is the treatment of choice for this patient?

371. A 53-year-old woman presents with complaints of weakness, anorexia, malaise, constipation, and back pain. While being evaluated, she becomes somewhat lethargic. Laboratory studies include a normal chest x-ray, serum albumin 3.2 mg/dL, serum calcium 14 mg/dL, serum phosphorus 2.6 mg/dL, serum chloride 108 mg/dL, blood urea nitrogen (BUN) 32 mg/dL, and creatinine 2.0 mg/dL. Which of the following is the most appropriate initial management?

372. Which of the following patients with primary hyperparathyroidism should undergo parathyroidectomy

373. A 45-year-old woman presents with hypertension, development of facial hair, and a 7-cm suprarenal mass. Which of the following is the most likely diagnosis?

374. A 44-year-old homeless woman presents to the emergency department because she is "bleeding from the breast." Physical examination shows a huge, fungating, ulcerated mass that occupies the entire right breast and is firmly attached to the chest wall. The right axilla is full of hard masses that are not movable either. Core biopsies of the breast are read as highly undifferentiated infiltrating ductal carcinoma, and assay for estrogen and progesterone receptors are negative. Which of the following is the most appropriate next step in management?

375. A 64-year-old woman complains of right calf pain and swelling. She recently underwent an uncomplicated left hemicolectomy for diverticular disease. A duplex ultrasound confirms the presence of deep vein thrombosis (DVT) of the calf. Which of the following is the most appropriate initial management of this patient?

376. For the first 6 hours following a long and difficult surgical repair of a 7-cm abdominal aortic aneurysm, a 70-year-old man has a total urinary output of 25 mL since the operation. Which of the following is the most appropriate diagnostic test to evaluate the cause of his oliguria?

379. A 66-year-old man presents with progressive jaundice, which he first noticed 6 weeks ago. He has a total bilirubin of 22 mg/dL, with a direct (conjugated) bilirubin of 16 mg/dL. His transaminases are minimally elevated, whereas his alkaline phosphatase is about six times the upper limit of normal. A sonogram shows dilated intrahepatic ducts, dilated extrahepatic ducts, and a very distended, thin-walled gallbladder without stones. Which of the following is the most appropriate next step in diagnosis?

382. A 45-year-old woman presents with a 7-cm renal cell carcinoma with radiologic evidence of abdominal lymph node involvement with no distant metastases. Which of the following is the most appropriate management of this patient?

383. A 58-year-old man is found to have high serum prostate–specific antigen (PSA) concentration with a normal prostate examination. A biopsy of the prostate confirms low-grade carcinoma. The patient wishes to avoid therapy involving any risk for impotence. Which of the following is the most appropriate management of this patient?

384. A 56-year-old man develops slow, progressive paralysis of the facial nerve on one side. It took several weeks for the full-blown paralysis to become obvious, and it has been present now for 3 months. It affects both the forehead and the lower face. He has no pain anywhere, and no palpable masses by physical examination. Which of the following is the most likely diagnosis?

385. A 28-year-old man with a past history of bilateral orchiopexy for cryptorchidism presents with a painless, unilateral right scrotal enlargement. On examination, there is a palpable right testicular mass and enlarged inguinal nodes. Scrotal ultrasonography demonstrates heterogeneity of the testis, with an associated hydrocele. A CT scan of the abdomen and pelvis demonstrated right-sided retroperitoneal adenopathy. CT scan of the chest is normal. Which of the following would help confirm the diagnosis?

386. A 28-year-old man with a past history of bilateral orchiopexy for cryptorchidism presents with a painless, unilateral right scrotal enlargement. On examination, there is a palpable right testicular mass and enlarged inguinal nodes. Scrotal ultrasonography demonstrates heterogeneity of the testis, with an associated hydrocele. A CT scan of the abdomen and pelvis demonstrated right-sided retroperitoneal adenopathy. CT scan of the chest is normal. Staging workup and surgery reveal a seminoma of the testicle, with positive inguinal and retroperitoneal nodes. Therapeutic management for this patient is which of the following?

388. A patient with mild skin pigmentation is admitted emergently to your service because of sudden abdominal pain, fever, and a rigid abdomen. Her blood work indicates a marked leukocytosis, a blood sugar of 55 mg/dL, a sodium value of 119 mEq/dL, and a potassium value of 6.2 mEq/dL. Her blood pressure is 88/58-mmHg. She undergoes an exploratory laparotomy. Which of the following is the definitive treatment for her primary condition?

389. The unrestrained front-seat passenger in a car that crashes sustains closed comminuted fractures of both femoral shafts. Shortly after admission, he develops a blood pressure of 80/50 mm Hg, a pulse rate of 110/min, and a venous pressure of zero. He becomes pale, cold, and clammy, but the rest of his physical examination and x-ray films of the chest and pelvis are unremarkable. A sonogram of the abdomen done in the emergency department is likewise negative. Which of the following is the most likely reason for the low blood pressure?

391. A 24-year-old patient with known neurofibromatosis type 2 undergoes an MRI for ringing in his ears. The MRI demonstrates lesions in bilateral auditory canals. Which of the following is the most likely diagnosis?

392. A40-year-old man with a history of alcohol abuse presents after an episode of binge drinking. He is complaining of epigastric pain, radiating to the back, associated with nausea and vomiting. On examination, he has marked tenderness in the epigastrium, with guarding, decreased bowel sounds, and moderate abdominal distention. Laboratory findings include leukocytosis and increased serum amylase and lipase. Abdominal roentgenograms demonstrate several dilated bowel loops in the upper abdomen. Select the most likely diagnosis.

393. A 65-year-old man presents with a 4-day history of worsening lower abdominal pain and constipation. On examination, he is febrile (38.5°C) and has lower abdominal tenderness that is most intense in the midline and left lower quadrant associated with a palpable fullness. Laboratory findings demonstrate a moderate leukocytosis and abdominal roentgenograms show an ileus pattern. Select the most likely diagnosis.

394. A 65-year-old man presents to the physician’s office with complaints of abdominal discomfort and jaundice for the past 3 weeks. Past history is pertinent for 30 pack-year smoking history, occasional alcohol intake, and a 5.5-mm ulcerating melanoma removed from his back 21/ 2 years ago. Examination reveals a mildly jaundiced patient with normal vital signs and a slightly distended abdomen with mild right upper quadrant tenderness and significant hepatomegaly. Which one is the most likely diagnosis?

395. A 45-year-old woman presents with left-sided weakness. A CT scan of the head demonstrates a well-circumscribed mass abutting the skull in the right hemisphere. Workup of the mass reveals a meningioma. Which of the following is the best next step in treatment?

396. A 30-year-old man presents to the emergency department with sudden onset of severe epigastric pain and vomiting 3 hours ago. He reports a 6-month history of chronic epigastric pain occurring nearly every day and relieved by antacids. On examination, he appears sweaty and avoids movement. Vital signs reveal a temperature of 100°F, BP of 100/60 mmHg, pulse rate of 110/min, and respiratory rate of 12/min. The remainder of his examination reveals diminished bowel sounds and a markedly tender and rigid abdomen. A chest x-ray and abdominal films reveal pneumoperitoneum. Which of the following is the most likely diagnosis?

397. A 15-year-old otherwise healthy female high school student begins to notice galactorrhea. A pregnancy test is negative. Which of the following is a frequently associated physical finding?

398. A 52-year-old woman sees her physician with complaints of fatigue, headache, flank pain, hematuria, and abdominal pain. She undergoes a sestamibi scan that demonstrates persistent uptake in the right superior parathyroid gland at 2 hours. Which of the following laboratory values is most suggestive of her diagnosis?

399. A 30-year-old man presents to the emergency department with sudden onset of severe epigastric pain and vomiting 3 hours ago. He reports a 6-month history of chronic epigastric pain occurring nearly every day and relieved by antacids. On examination, he appears sweaty and avoids movement. Vital signs reveal a temperature of 100°F, BP of 100/60 mmHg, pulse rate of 110/min, and respiratory rate of 12/min. The remainder of his examination reveals diminished bowel sounds and a markedly tender and rigid abdomen. A chest x-ray and abdominal films reveal pneumoperitoneum. Which of the following is the most appropriate next step in management?

400. A 55-year-old man presents to the physician’s office complaining of upper abdominal pain of 2 months’ duration. The pain is described as gnawing, localized to the upper midline, and associated with nausea. The pain is exacerbated by food, and there is an associated 20-lb weight loss over 2 months. His past history is pertinent for a 30 pack-year smoking history, occasional alcohol intake, and a prior history of a benign gastric ulcer 5 years ago. Physical examination reveals normal vital signs, mild epigastric pain with deep palpation, and mildly hemepositive stool. An evaluation for recurrence of a gastric ulcer is recommended. Which of the following tests is the most reliable method for diagnosing a gastric ulcer?

401. A middle-aged homeless man is brought to the ER by EMS for altered mental status, seizures, and vomiting. On physical examination he has no fever, neck stiffness, or evidence of head trauma. He does, however, have multiple dental caries and a focal neurologic deficit. Which of the following is the best next step in the patient’s workup?

403. A 49-year-old woman presents to her physician with dysphagia, regurgitation of undigested food eaten hours earlier, and coughing over the last 6 months. She was hospitalized 1 month ago for aspiration pneumonia and successfully treated with antibiotics. Examination reveals a thin-appearing woman with normal vital signs and unremarkable chest, heart, and abdominal examination. A UGI contrast study is performed and reveals a pharyngoesophageal (Zenker’s) diverticulum. Which of the following statements is true regarding Zenker’s diverticula?

404. A 30-year-old man presents to the emergency department with sudden onset of severe epigastric pain and vomiting 3 hours ago. He reports a 6-month history of chronic epigastric pain occurring nearly every day and relieved by antacids. On examination, he appears sweaty and avoids movement. Vital signs reveal a temperature of 100°F, BP of 100/60 mmHg, pulse rate of 110/min, and respiratory rate of 12/min. The remainder of his examination reveals diminished bowel sounds and a markedly tender and rigid abdomen. A chest x-ray and abdominal films reveal pneumoperitoneum. Which of the following is the most appropriate next diagnostic test?

405. An 18-year-old high school senior develops peripheral vision abnormalities. A CT scan of the brain reveals a cystic suprasellar mass with some calcification noted. Clinically, this is compatible with a craniopharyngioma. What is the best next step in treatment?

406. A 65-year-old diabetic man presents to the emergency department with a history of a penetrating wound to his buttock by a wooden stump while working in his garden 24 hours earlier. On examination, he is febrile, the tissue around the wound is violaceous in color, and several bullae and crepitus are noted in the buttock. The drainage from the wound is foul smelling, watery, and grayish in appearance. The optimal treatment for this patient would include which of the following?

407. A 36-year-old woman whose mother has just undergone treatment for breast cancer is asking about how this affects her and what can be done to lessen her chances of having the disease. Which of the following has the lowest risk factor for breast cancer?

408. A 26-year-old man is brought to the emergency room after being extricated from the driver’s seat of a car involved in a head-on collision. He has a sternal fracture and is complaining of chest pain. He is hemodynamically stable and his electrocardiogram (ECG) is normal. Which of the following is the most appropriate management strategy for this patient?

409. A 76-year-old man is undergoing an abdominoperineal resection for rectal cancer. During the surgery, unexpected severe bleeding is encountered, and the patient is hypotensive on and off for almost an hour. The anesthesiologist notes ST depression and T-wave flattening on the ECG monitor. Which of the following is the most likely diagnosis and the expected mortality?

410. A 65-year-old man presents to the physician’s office for his yearly examination. His past history is pertinent for a 40 pack-year smoking history and colon cancer 3 years ago for which he underwent a sigmoid colectomy. The most recent colonoscopic follow-up 3 months ago was negative. His physical examination is normal. Laboratory results show a normal CBC and electrolytes, markedly elevated cholesterol, and a CEA of 12 compared to values of less than 5 obtained every 6 months since colectomy. A repeat CEA 4 weeks later was 15, and liver function tests revealed a minimally elevated alkaline phosphatase, with normal transaminases and bilirubin. Which of the following is the most appropriate next diagnostic test in this patient?

411. The imaging studies demonstrate three lesions in the right hepatic lobe suspicious for metastatic disease, each measuring 3–4 cm in diameter. There was no evidence of extrahepatic disease. Which of the following is the most appropriate next step in management?

412. In your discussion with the patient regarding the risks and benefits of the different management options listed above, which of the following values should you quote regarding the expected 5-year survival rate following curative surgical resection?

413. A 60-year-old man is admitted to the coronary care unit with a large anterior wall myocardial infarction. On his second hospital day, he begins to complain of the sudden onset of numbness in his right foot and an inability to move his right foot. On physical examination, the right femoral, popliteal, and pedal pulses are no longer palpable. The left lower extremity is normal. Which of the following is the most appropriate management of this patient?

415. A 46-year-old woman, who had always been in good health, comes in because of the sudden onset of very severe back and leg pain that she experienced 2 hours ago when attempting to lift a heavy object. She says that she felt "a bolt of lightening" running down the back of her leg, and she still has very severe pain that prevents her from walking or moving. The pain is exacerbated by coughing, sneezing, or straining. She keeps the affected leg flexed; straight leg raising gives her excruciating pain. She has good sphincteric tone and intact sensation in the perineum. Once the diagnosis is confirmed with the appropriate studies, which of the following will be the most appropriate treatment?

416. During diagnostic evaluation, a 14-year-old girl with menorrhagia, frequent nosebleeds, and iron deficiency anemia is found to have a low platelet count with a normal coagulation profile. Bone marrow biopsy reveals abundant megakaryocytes. On abdominal examination, no organomegaly is noted. Which of the following is the most appropriate initial therapy for this patient?

417. A 34-year-old woman has recurrent fainting spells induced by fasting. She also reports palpitations, trembling, diaphoresis, and confusion prior to the syncopal episodes. She has relief of symptoms with the administration of glucose. Which of the following findings is most consistent with the diagnosis of an insulinoma?

418. A 70-year-old woman undergoes a cardiac catheterization for exertional chest pain. Her pain continues to worsen and she is interested in having either surgery or percutaneous coronary intervention (PCI). Which of the following would be an indication for her to undergo either coronary artery bypass grafting or PCI?

419. Six months ago at the time of lumpectomy for breast cancer, a 60-year-old female attorney quit a 30-year smoking habit of 2 packs per day. She had the chest radiograph shown here as part of her routine follow-up examination. Based on her age and history of smoking, you are concerned for either a new primary lung or metastatic breast malignancy. Which of the following is the most appropriate next step in the management of this lesion?

420. A 72-year-old woman has a red, swollen breast. She states that the condition has been present for at least several weeks, perhaps a month or two. She has no pain or fever. The skin over the area looks like orange peel. The area is not warm to the touch, but on physical examination there is a fullness to the entire breast, with no discrete mass. Which of the following is the most likely diagnosis?

421. A 39-year-old woman presents to the physician’s office for evaluation of a palpable nodule in the neck of 2 years’ duration. Her past history is pertinent for Hashimoto’s disease diagnosed 5 years ago, for which she takes thyroid hormone. She has a history of low-dose chest irradiation for an enlarged thymus gland during infancy. On examination, a 2.5-cm nodule is palpable in the left lobe of the thyroid and is firm and nontender. Which of the following portions of her history increases the risk for thyroid cancer?

422. A 39-year-old woman presents to the physician’s office for evaluation of a palpable nodule in the neck of 2 years’ duration. Her past history is pertinent for Hashimoto’s disease diagnosed 5 years ago, for which she takes thyroid hormone. She has a history of low-dose chest irradiation for an enlarged thymus gland during infancy. On examination, a 2.5-cm nodule is palpable in the left lobe of the thyroid and is firm and non-tender. Which of the following is the most appropriate next step in her management?

424. A 58-year-old man presents with tachycardia, fever, confusion, and vomiting. Workup reveals markedly elevated (triiodothyronine) T 3 and (thyroxine) T4 levels. He is diagnosed as having a thyroid storm. Which of the following is the most appropriate next step in the management of this patient?

425. A 34-year-old woman presents with hypertension, generalized weakness, and polyuria. Her electrolyte panel is significant for hypokalemia. Which of the following is the best initial test given her presentation and laboratory findings?

426. A 35-year-old man falls on an outstretched hand and comes in complaining of wrist pain. He relates that he was not able to break the fall, and that the heel of his hand took the brunt of his full weight as it hit the pavement. On physical examination, he is distinctly tender to palpation over the anatomic snuff box. Anteroposterior and lateral x-rays are negative. Which of the following are the most likely diagnosis and most appropriate next step in management?

429. An 18-year-old football player is seen in the emergency ward with severe knee pain incurred after being hit by a tackler while running. Which of the following findings on physical examination is most sensitive for an anterior cruciate ligament injury?

430. A 34-year-old man is extricated from an automobile after a motor vehicle collision. The patient has an obvious deformity of his right thigh consistent with a femur fracture. Upon closer examination of the right thigh, there is bone visible through an open wound. Which of the following is the most appropriate management of his open femur fracture?

431. A 43-year-old woman comes in because of a breast mass. Two days ago, she noticed a lump on self-examination. She has a 2-cm, firm, nontender mass in the left breast, which is movable from the chest wall, but not movable within the breast. She has no prior history of breast disease, but she is well read and well informed, and she specifically requests that a biopsy be done with a mammotome. Before proceeding, which of the following is the most appropriate initial step?

432. A 55-year-old woman presents with a 6-cm right thyroid mass and palpable cervical lymphadenopathy. Fine-needle aspiration (FNA) of one of the lymph nodes demonstrates the presence of calcified clumps of sloughed cells. Which of the following best describes the management of this thyroid disorder?

433. A 45-year-old woman is found to have suspicious appearing calcifications in the right breast on a screening mammogram. Stereotactic biopsy of the calcifications shows lobular carcinoma in situ (LCIS). On examination both breasts are dense without palpable masses. The neck and bilateral axilla are negative for lymphadenopathy. Which of the following is the most appropriate management of this patient?

434. A30-year-old man presents with sudden onset of severe epigastric pain 6 hours ago. Examination reveals a low-grade fever, tender abdomen throughout, with rigidity of the abdominal usculature. Abdominal roentgenograms show pneumoperitoneum. Select the most likely diagnosis.

435. A 40-year-old woman presents to the emergency room with a 3-day history of worsening abdominal pain, with nausea and vomiting. Examination reveals a low-grade fever and abdominal tenderness in the right upper quadrant with guarding, especially during inspiration. Laboratory findings include a mild leukocytosis and a slightly elevated bilirubin. Select the most likely diagnosis.

436. A 3-year-old boy presents to the physician’s office with an asymptomatic neck mass located in the midline, just below the level of the thyroid cartilage. The mass moves with deglutition and on protrusion of the tongue. Which one is the most likely diagnosis?

437. While playing with his children, a 44-year-old man falls and lands on his right shoulder. There is immediate pain and deformity. In an uncomplicated dislocation of the glenohumeral joint, the humeral head usually dislocates primarily in which of the following directions?

439. In a failed suicide gesture, a depressed student severs her radial nerve at the wrist. Which of the following is her expected disability?

440. A 32-year-old, previously healthy man is a victim of a drive-by shooting, sustaining a gunshot wound to the left lower extremity. The entrance wound is located over the medial aspect of the calf, with an exit wound over the anterior pretibial region. Neurovascular examination of the extremity is normal. There is associated soft-tissue injury from the blast effect and a severely comminuted tibial fracture demonstrated on radiographs. Appropriate management of this injury includes which of the following?

441. A 16-year-old girl with a history of ulcerative colitis managed with steroid therapy presents to the emergency department with a 36-hour history of nausea, crampy abdominal pain, and severe bloody diarrhea. On examination, the patient is febrile and pale, with a blood pressure of 90/60 mmHg and heart rate of 130 beats/min. Her abdomen is distended and diffusely tender. A complete blood count (CBC) demonstrates a leukocytosis with a left shift. The patient receives IV fluid resuscitation and nasogastric (NG) tube decompression.Further therapeutic interventions should include which one of the following?

443. A 16-year-old adolescent boy sustains head trauma in a motor vehicle collision. He has a GCS of 15 and an obvious depressed skull fracture with 1cm displacement. During his hospital stay, he notices clear fluid draining from his nose. What is the best management strategy for this patient?

445. A 50-year-old woman presents to the physician’s office for evaluation of a right neck mass. The mass has been present for 3 years and is painless. On examination, a nontender, firm, 2.5-cm mass is noted slightly below and posterior to the angle of the mandible on the right. Which one is the most likely diagnosis?

446. A 35-year-old woman presents to the physician’s office for evaluation of a left neck mass discovered 1 month ago on a routine physical examination. On examination, the mass measures 2 cm and is located anterolateral to the larynx and trachea. It is nontender and moves with swallowing. Past history is pertinent for a 15 pack-year smoking history and occasional alcohol intake. Which one is the most likely diagnosis?

447. A 55-year-old man presents to the physician’s office with complaints of hoarseness and left neck fullness for the past month. On examination, a firm, movable, left submandibular mass is noted. Past history is pertinent for a 30 packyear smoking history with occasional alcohol intake. Which one is the most likely diagnosis?

448. A 41-year-old woman has noted bilateral thin serous discharge from her breasts. There seems to be no mass associated with it. Which of the following statements would be appropriate to tell the patient?

449. A 52-year-old woman presents with hypertension, obesity, and new skin striae. You are concerned about possible Cushing syndrome. Which of the following is the most common cause of Cushing syndrome?

451. A severely traumatized woman is seen in the emergency room (ER) with decreased mental status. Prior to intubation, she does not open her eyes, withdraws with all of her extremities, and makes incomprehensible sounds. What is her Glasgow coma scale score?

452. A 50-year-old man presents to the emergency department for increasing abdominal distention and jaundice over the last 4–6 weeks. Examination reveals mild jaundice, spider angiomas, and ascites. Enlarged veins are noted around the umbilicus. Which one is the most likely diagnosis?

453. A 75-year-old man is brought to the emergency department by his family for evaluation of jaundice. He complains of pruritus of 2 weeks’ duration and a recent 10-lb weight loss. On examination, he is deeply jaundiced and has a nontender, globular mass in the right upper quadrant of the abdomen that moves with respiration. Which one is the most likely diagnosis?

454. A 75-year-old woman is brought to the emergency department from the nursing home for jaundice and mental confusion. The nursing home notes state that she has become less responsive and has developed jaundice over the last 2 weeks. Past history is pertinent for hypertension, diabetes, and prior colon resection for cancer at age 55. Examination reveals mild jaundice with vital signs of temperature 101.5°F, pulse rate 110/min, and BP 100/60 mmHg. She does not respond to verbal commands, but withdraws to pain. Abdominal examination reveals tenderness in the epigastrium and right upper quadrant. Which one is the most likely diagnosis?

455. An 18-year-old man is admitted to the ER following a motorcycle accident. He is alert and fully oriented, but witnesses to the accident report an interval of unresponsiveness following the injury. Skull films disclose a fracture of the left temporal bone. Following x-ray, the patient suddenly loses consciousness and dilation of the left pupil is noted. Which of the following is the most likely diagnosis?

456. A 42-year-old woman presents to the ER with the worst headache of her life. A noncontrast CT scan of the head is negative for lesions or hemorrhage. She then undergoes a lumbar puncture, which appears bloody. All 4 tubes collected have red blood cell counts greater than 100,000/mL. Which of the following steps is the most appropriate management of this patient?

457. A trauma patient with a closed-head injury is being monitored in the neurosurgical intensive care unit (ICU). His ICP measurement is seen to rise precipitously. An acute increase in ICP is characterized by which of the following clinical findings?

460. After being injured by a bull on his mother’s farm, a young man is placed in a cast for a supracondylar fracture of his humerus. A few hours later he begins to experience intense pain, swelling, and weakness in the ipsilateral hand. Pulses are normal in bilateral upper extremities. Which of the following is the most appropriate initial management of this patient?

461. A 39-year-old man presents with an isolated fracture of the tibia after being hit on the leg with a car. The patient is stable and a radiograph of the leg shows a tibial shaft fracture with severe dislocation. Which of the following is the most appropriate management of the fracture?

462. A 45-year-old man presents to the physician’s office for evaluation of a posterior neck mass. The mass has been present for years, but has slowly enlarged over the last 2 years. Examination reveals a subcutaneous mass that is soft, nontender, and movable. Which one is the most likely diagnosis?

463. A 6-year-old boy presents to the emergency department with a cough, sore throat, and malaise of 4 days’ duration. Examination reveals a temperature of 101.5°F, erythematous pharynx, and a tender right neck mass with overlying erythema. Which one is the most likely diagnosis?

464. An 18-month-old girl is brought to the physician’s office for evaluation of left neck mass. Examination reveals a 2-cm soft, nontender, fluctuant mass in the left lateral neck. This is located at the anterior border of the sternomastoid, midway between the mastoid and clavicle. Which one is the most likely diagnosis?

465. A 63-year-old woman notices lumps on both sides of her neck. A fine-needle aspirate is nondiagnostic, and she undergoes total thyroidectomy. Final pathology reveals a 2-cm Hürthle cell carcinoma. Which of the following is the most appropriate postsurgical management of this patient?

466. A 51-year-old man presents with a 2-cm left thyroid nodule. Thyroid scan shows a cold lesion. FNA cytology demonstrates follicular cells. Which of the following is the most appropriate initial treatment of this patient?

467. A 25-year-old man is stabbed once in the right chest. The entrance wound is on the midaxillary line, at the level of the fifth intercostal space. He arrives at the emergency department moderately short of breath, but he is fully awake and alert, is talking with a normal tone of voice, and has no distended veins visible in his neck or forehead. His blood pressure is 130/75 mm Hg, and his pulse is 82/min. Physical examination of the chest shows the wound, which is not visibly "sucking air," and demonstrates no breath sounds at all on the right side, which is tympanitic to percussion. There is no evidence of mediastinal displacement. Which of the following would be the most appropriate next step in management?

471. A 6-year-old boy is brought into the emergency room by his mother for walking with a limp for several weeks. On examination, the patient has tenderness over his right thigh without evidence of external trauma. An x-ray of the pelvis shows a right femoral head that is small and denser than normal. Which of the following is the most likely diagnosis?

472. A 65-year-old man presents with acute onset of pain, swelling, and erythema of the left knee. He denies previous episodes or trauma to the knee. The differential diagnosis includes septic arthritis and gout. Which of the following is the best study to differentiate between gout and septic arthritis?

473. A 40-year-old previously healthy man presents with sudden onset of severe abdominal pain that radiates from the right loin (flank) to groin. This pain is associated with nausea, sweating, and urinary urgency. He is distressed and restless, but an abdominal examination is normal. Which of the following is the most appropriate next step in management?

474. A 25-year-old woman was involved in a motor vehicle crash and sustained a significant closed-head injury, a pulmonary contusion, and a pelvic fracture. She is unresponsive and is ventilated in the intensive care unit (ICU). Which of the following is the best initial approach to the management of this patient’s nutritional needs?

475. A young mother is at the pediatrician's office for a routine well-baby visit for her 18-month-old son. It is immediately noticed that one of the baby's pupils is white, while the other one is black. When asked about it, the mother relates that she saw that curious situation for the first time 1 week ago, but since the baby was otherwise asymptomatic, she did not think it merited special attention. Which of the following is the most appropriate course of action?

476. Incisional biopsy of a breast mass in a 35-year-old woman demonstrates cystosarcoma phyllodes at the time of frozen section. Which of the following is the most appropriate management strategy for this lesion?

477. A 36-year-old woman, 20 weeks pregnant, presents with a 1.5-cm right thyroid mass. FNA is consistent with a papillary neoplasm. The mass is cold on scan and solid on ultrasound. Which of the following methods of treatment is contraindicated in this patient?

478. A 45-year-old man presents to the physician’s office complaining of dysphagia and retrosternal pressure and pain of 2-year duration. The symptoms have worsened over the last 3 months. He has a 30 pack-year smoking history and drinks beer on weekends. Vital signs include a BP of 150/90 mmHg, pulse rate of 90/min, and respiratory rate of 12/min, with a normal temperature. Examination reveals a thin man with a normal heart, lung, and abdomen examination. An esophagogram reveals a 6-cm, smooth, concave defect in the midesophagus with sharp borders. Esophagoscopy reveals intact overlying mucosa and a mobile tumor. Which of the following is the most likely diagnosis?

479. A 45-year-old man presents to the physician’s office complaining of dysphagia and retrosternal pressure and pain of 2-year duration. The symptoms have worsened over the last 3 months. He has a 30 pack-year smoking history and drinks beer on weekends. Vital signs include a BP of 150/90 mmHg, pulse rate of 90/min, and respiratory rate of 12/min, with a normal temperature. Examination reveals a thin man with a normal heart, lung, and abdomen examination. An esophagogram reveals a 6-cm, smooth, concave defect in the mid-esophagus with sharp borders. Esophagoscopy reveals intact overlying mucosa and a mobile tumor. Which of the following is the most appropriate next step?

480. During the performance of a supraclavicular node biopsy under local anesthesia, a hissing sound is suddenly heard, and the patient suddenly dies. At the time of the catastrophic event, the target node was under traction, and the final cut was being made blindly behind it to free it up completely. The patient, an otherwise healthy 24-year-old man, was inhaling at that moment. Which of the following most likely caused this patient's death?

481. A 42-year-old man presents with a solitary lung lesion. At the time of operation on this patient, a firm, rubbery lesion in the periphery of the lung is discovered. It is sectioned in the operating room to reveal tissue that looks like cartilage and smooth muscle. Which of the following is the most likely diagnosis?

482. A 45-year-old woman presents with dysphagia, regurgitation of undigested food, and weight loss. She had x-rays shown here as part of her workup. Upper endoscopy reveals no evidence of malignancy and esophageal motility studies show incomplete lower esophageal sphincter relaxation. Which of the following is the next best step in the treatment of this patient?

483. During diagnostic evaluation, a 14-year-old girl with menorrhagia, frequent nosebleeds, and irondeficiency anemia is found to have a low platelet count with a normal coagulation profile. Bone marrow biopsy reveals abundant megakaryocytes. On abdominal examination, no organomegaly is noted. The patient has a satisfactory response to the initial therapeutic intervention, but over 6–12 months’ time, the response is less dramatic and shorter in duration. There are signs and symptoms of increasing side effects from therapy. The next step in management should be to recommend which of the following?

484. A 70-year-old man is admitted to the ICU after repair of an abdominal aortic aneurysm. He has a prior history of hypertension and mild congestive heart failure, which were adequately controlled with digoxin and diuretics. To facilitate perioperative management, a Swan-Ganz (multilumen pulmonary artery) catheter was inserted in the operating room. During the first few hours postoperatively, the patient is noted to have a blood pressure of 140/70 mmHg, heart rate of 110/min, flat neck veins, a pulmonary arterial wedge pressure of 9 mmHg, and poor urine output. Which of the following is the most appropriate next step in management of this patient?

485. A 70-year-old man is admitted to the ICU after repair of an abdominal aortic aneurysm. He has a prior history of hypertension and mild congestive heart failure, which were adequately controlled with digoxin and diuretics. To facilitate perioperative management, a Swan-Ganz (multilumen pulmonary artery) catheter was inserted in the operating room. During the first few hours postoperatively, the patient is noted to have a blood pressure of 140/70 mmHg, heart rate of 110/min, flat neck veins, a pulmonary arterial wedge pressure of 9 mmHg, and poor urine output. Several hours after this intervention a bolus of IV crystalloid, the patient is reassessed. The blood pressure is 150/85 mmHg, heart rate is 90/min, neck veins are distended, and the pulmonary arterial wedge pressure is 17 mmHg. Urine output is still low in volume. At this point, management should be which of the following?

486. A 19-year-old previously healthy man is an unbelted driver of a motor vehicle involved in a front-end collision. On arrival in the emergency department, the patient is noted to have stridor, with marked respiratory distress, and an oxygen saturation of 88% despite 100% oxygen by mask. He has obvious extensive facial injuries, a flail chest, and poor chest expansion. Bag-mask-valve ventilation is ineffective. Which of the following is the most appropriate next step in management?

487. A 14-year-old boy slides down a banister and crashes into a large ornamental knob at its base, thereby injuring his scrotal contents. He presents in the emergency department with acute testicular pain and a scrotal hematoma the size of a grapefruit. He is able to void normally, and his urine does not contain blood. A rectal examination is unremarkable. Findings from which of the following tests will most likely determine further therapy?

488. A 32-year-old man presents with an asymptomatic mass in his right testicle. On examination, the mass cannot be transilluminated. Ultrasound shows a solid mass in the right testicle. Which of the following is the most accurate method in obtaining a diagnosis of testicular cancer?

489. A 10-year-old boy presents to the emergency room with pain in the left testicle. The pain was acute in onset and began 1 hour ago. On physical examination, he is noted to have a high-riding, firm, and markedly tender left testis. The right testicle is normal. Urinalysis is unremarkable. Which of the following is the most appropriate management of this patient?

490. A pedestrian is hit by a speeding car. Radiologic studies obtained in the emergency room, including a retrograde urethrogram (RUG), are consistent with a pelvic fracture with a rupture of the urethra superior to the urogenital diaphragm. Which of the following is the most appropriate next step in this patient’s management?

491. A 55-year-old man presents with fever and pain in the perineal region. Upon further questioning he also complains of frequency, urgency, dysuria, and a decreased urinary stream. On physical examination his abdomen is soft, nondistended, and nontender. Digital rectal examination demonstrates exquisite tenderness on the anterior aspect. Laboratory examination reveals leukocytosis and findings on urinalysis are consistent with a bacterial infection. Which of the following is the most likely diagnosis?

492. A previously healthy 45-year-old man presents with a 9-month history of a slow-growing, painless right neck mass. He is a nonsmoker and has no significant past medical history. On examination, there is a nontender, discrete, 3-cm mass over the angle of the right mandible. Facial muscle function and sensation are normal. An oropharyngeal examination is normal. Which of the following is the most likely diagnosis?

493. A previously healthy 45-year-old man presents with a 9-month history of a slow-growing, painless right neck mass. He is a nonsmoker and has no significant past medical history. On examination, there is a nontender, discrete, 3-cm mass over the angle of the right mandible. Facial muscle function and sensation are normal. An oropharyngeal examination is normal. Which of the following is the best next step in the management of this patient?

495. A 44-year-old woman has a palpable nodule in the right lobe of her thyroid gland. The nodule measures 2 cm and is firm. The rest of the thyroid gland cannot be felt and is not tender. She also describes losing weight in spite of a ravenous appetite, palpitations, and heat intolerance. She is thin, fidgety, and constantly moving, with moist skin and a pulse of 105/min. She has no exophthalmos or pretibial edema. Her TSH is reported as much lower than normal, and she has elevated levels of free T4. Which of the following is the most appropriate next step in diagnosis?

496. A 63-year-old man underwent a 3-vessel coronary artery bypass graft (CABG) 5 hours ago. Initially, his mediastinal chest tube output was 300 mL blood/h, but an hour ago, there was no further evidence of bleeding from the tube. His mean arterial pressure has fallen, and several fluid boluses were administered. His central venous pressure (CVP) is elevated to 20 mm Hg, and he has required the addition of inotropes. Which of the following is the best management strategy?

497. An 89-year-old man has lost 30 lb over the past 2 years. He reports that food frequently sticks when he swallows. He also complains of a chronic cough. Barium swallow is shown here. What is the best treatment option for this patient?

498. A 23-year-old man presents to the emergency department with a soft-tissue injury to the left lower extremity. The injury was sustained 8 hours earlier in a motorcycle accident on a gravel road. On examination, the patient has a 7-cm deep laceration to the calf, with visible road debris. He had full tetanus immunization as a child and a tetanus booster immunization at age 15. Appropriate management of this injury would include which of the following?

499. A 6-year-old boy presents to the emergency department with a painful, markedly swollen elbow. While ice-skating, he fell with his arm outstretched. Radiographs of the elbow demonstrate a displaced, supracondylar fracture of the humerus. On examination, there is pain on passive flexion at the wrist and a decreased radial pulse, with diminished capillary refill in the hand. Which of the following is the most appropriate management of this injury?

500. A 25-year-old man is stabbed in the right chest. He comes in fully awake and alert, and, in a normal tone of voice, he states that he feels short of breath. His vital signs are normal and stable. On physical examination, he has no breath sounds at the right base, and only faint breath sounds at the apex. He is dull to percussion over the right base. A chest x-ray film confirms that he has a hemothorax on that side. Which of the following is the most appropriate next step in management?

458. A 16-year-old girl with a history of ulcerative colitis managed with steroid therapy presents to the emergency department with a 36-hour history of nausea, crampy abdominal pain, and severe bloody diarrhea. On examination, the patient is febrile and pale, with a blood pressure of 90/60 mmHg and heart rate of 130 beats/min. Her abdomen is distended and diffusely tender. A complete blood count (CBC) demonstrates a leukocytosis with a left shift. The patient receives IV fluid resuscitation and nasogastric (NG) tube decompression. We inject high-dose IV steroids and broad-spectrum antibiotics. After 48 hours, there is no clinical improvement. Which of the following is the most appropriate next step in management?

442. A 60-year-old otherwise healthy woman presents to her physician with a 3-week history of severe headaches. A contrast CT scan reveals a small, circular, hypodense lesion with ringlike contrast enhancement. Which of the following is the most likely diagnosis?